The etiology of deafness in human is both genetic and environmental. The prevalence of deafness in live births is 1:1000 and among them 60% is genetic. Connexin 26 gene mutations are the most common cause of inherited deafness and account for about 40% of the genetic cases. In two conditions in human the coexistence of hypothyroidism and deafness were reported; Pendred syndrome and thyroid hormone resistance syndrome.